


Butterfly on Your Right Eye

by Nillas NSFW Corner (Agraulis_vanillae)



Category: Undertale (Video Game)
Genre: Angsty Sans, Body Horror, Boogeyman W. D. Gaster, Emotional Hurt/Comfort, Fontcest, Genocide Route Reference, Hurt/Comfort, M/M, Nightmares, Panic Attacks, Psychological Trauma, Songfic, Soul Sex
Language: English
Status: Completed
Published: 2016-03-21
Updated: 2016-03-21
Packaged: 2018-05-28 03:46:08
Rating: Mature
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 2,100
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6314098
Author URL: https://archiveofourown.org/users/Agraulis_vanillae/pseuds/Nillas%20NSFW%20Corner
Summary: <blockquote class="userstuff">
              <p>Very obviously inspired by Butterfly on Your Right Shoulder. Sans wakes from a particularly bad nightmare.</p>
            </blockquote>





	Butterfly on Your Right Eye

**Author's Note:**

> I was assisted by Angel Irae (Bros Boning) on this story, so if you like what you've read here, maybe you ought to check out her stories! She's currently working on Re:Tale.

Sans writhed in his bed, sheets long kicked away, and the fabric of his pillow sticking to his sweaty forehead. Asleep, the only defense he had against the movie playing out in his minds eye was for his body to twitch rapidly and groan in trepidation.

The judgment hall glowed its characteristic gold, the old rune symbols hovering omniscient throughout the stained glass windows. He could see the human child at the end of the hall, somehow shadowed even in the presence of so much light. However, in the blink of the eye, the kid had all but sprinted close and it was all he could do to dodge the swipe of the knife. Feeling exhaustion hit him like a truck, he needed to move back and put some space between him and the eerie glow of the child's expressionless eyes but found he couldn't. Feeling an unexpected pull across his body when he leaned back, he realized it wasn't exhaustion after all, but that he truly couldn't move.

A golden flower had sprouted from the non-existent cracks between tiles and wrapped itself across his arms and legs, thoroughly twining between the gaps in his radius and ulna, and with a forceful snap holding his chest out by the angle held on his arms. Any attempts to even side step, fall back, or dash forward was restrained by the vines anchoring him through the tibia and fibula. The demon pretending to be a human now stepped forward slowly, taking their time. He could hear the flower slipping into his skull through the base of his spine, petals brushing the vertebrae insidiously, saying-

“Golly, you didn't think I'd let you get away THAT easily, did you Smiley Trashbag?” with the high pitched put-on cheer resonating hollowly through his skull.

Then the fight was over. Without his ability to dodge, and too entangled to simply “shortcut” away, his personal demon wasted no more time driving the knife through his jacket into his chest, and shattering the bone caught in its path. His voice caught and no screams, no whimpers bled through. Instead, a bright red fluid seeped from his broken bones and not for the first time he wondered if that was the physical manifestation of raw LOVE.

He shook, bones rattling and severed joints clicking, but he couldn't even fall to his knees as the vines tightened across his body, forcing him to simply hang there-

-and suddenly it wasn't the child that was standing in front of him but Gaster, the crack across his skull fluttering oddly. As he watched disjointedly, it pulled off from Gaster's skull as a butterfly only to dissolve into dust as Gaster reached into his lacerated rib cage, pulling it apart. Excruciating pain laced through his being from the unnatural movement pressed harshly throughout his vertebrae, the sudden shock dizzying him even as he gagged on the vines that choked back the impending scream. For an instant, he could feel his soul beating frantically with icy cold fear laced across each pulse, exposed and vulnerable to the fading monster...

… and suddenly he was up, thrashing wildly against Papyrus's hold.

“SANS!! SANS YOU'RE OKAY, IT WAS JUST A NIGHTMARE, YOU'RE OKAY-” Papyrus chanted softly to him, like a mantra, not letting Sans startle out of his arms. He stopped struggling, and for a minute he laid there limply in his brother's arms, breathing heavily. Papyrus continued to murmur softly and hold him tight.

“i'm all right,” Sans repeated, not feeling at all right but letting Papyrus know that he was out of the nightmare.

“YOU WERE SCREAMING,” he responded, watching Sans with intense concern. Sans didn't want to think about it, the dream reality melting away quickly from his mind and good riddance, but he couldn't stop his damned tremors, bones rattling lowly in the faded light that escaped from his open door.

“it doesn't matter,” Sans dismissed, focusing on not thinking or solidifying the specter anymore than he already has, following the vague suspicion that possibly this wasn't just a dream but...

“DON'T SAY THAT SANS, IT DOES MA-”

Impulsively, Sans shoved his mouth to Papyrus's to prevent him from finishing that sentence. He could not allow *that maybe what he was seeing was memories* these night terrors to take shape. They remained like that for a heartbeat or two, stunned. His desperate gaze widened as Papyrus slowly held Sans' head in place and gently pushed his head forward. Sans could feel a lick of burning sensation across his soul and then an instantaneous alarmed ring of panic through his skull. He pushed backward, against Papyrus's hold and Papyrus moved his face away to stare searchingly.

“IT DOES MATTER,” Papyrus finished softly, and despite himself Sans had trouble reading the meaning behind those words. Ragged from the dream, he had no defense against the panic that laced through his mind, extinguishing that fiery yearning that dared to manifest itself for only the smallest sense of relief before he felt himself begin to hyperventilate.

Papyrus released his hold on Sans body to give him space, “BREATHE SANS, WHATEVER IT IS-”

Sans stepped away, determined not to let his bro see him have a breakdown and blipped, taking advantage of his freedom to take a shortcut into his sentry station in Snowdin forest. Sitting underneath the station, he curled his knees closed and felt his chest heaving, air wheezing through his teeth. Why did he have to kiss Papyrus? Why couldn't he just use his words and tell him kindly to PLEASE shut up before he attracted the man who spoke in hands? Hell, why couldn't he force himself to teleport further away so that he could come back when he was ready to face his brother? The panic attack ripped through him mercilessly, and when an unexpected warmth dripped from his eye sockets, he realized that he was sobbing silently. The intensity of his chest tightening suddenly and a lightheaded rush made him fall against the back of the station.

Feeling like he did, time seemed to warp and bend making it impossible to determine how long he'd endured the throes of his panic attack. When it finally ended, his panting slowly ending and a buzzing in his head, he faded out not quite asleep yet not 'present' either. The snow made it easier to succumb to the mental blankness, his state of mind matching the unperturbed whiteness.

He heard the crunching in the snow long before he saw Papyrus lean over the station to check for him. “SANS!”

“hey bro,” he vocalized softly.

Papyrus hopped over the station, and practically tackled him, “SANS WHAT IN THE ACTUAL HECK! DON'T SCARE ME LIKE THAT!”

Sans was too low energy to consider escaping his brother's ire for a few more hours. Instead, he nodded along foggily to Papyrus scolding, until Papyrus started brushing off frost and snow that stuck encrusted onto his jacket. He leaned forward into the attention silently, and Papyrus snaked an arm between his legs and chest, forcing him to relax the tension he'd held across his body through the fetal position.

The shift in tone faltered, and before long Papyrus had fallen silent too. He seemed to study Sans, and slowly leaned forward. Sans realized too late that this confrontation that he'd put off so long was now unavoidable. He was pinned underneath his station, and more so, lacked the energy to break off.

Papyrus pressed his mouth to his mouth, taking the lead and the red hot sparking feeling in his soul rose up with unexpected intensity. He moaned helplessly at the sensation and Papyrus slipped a hand underneath his shirt to rub his palm-like bones against San's ribs. Sans wanted to tell Papyrus that he didn't know what he was getting into, to find someone who didn't spend their nights feeling like they'd either be flayed wide open or hiding away in stark terror of their own feelings. He wanted to tell him to find someone healthier, mentally and physically but the look on Papyrus's face said that he wasn't about to let himself be pushed away so easily.

“pap pleas- hhAHH~” he shuddered uselessly against the firm hold that Papyrus made across a rib, thumb bones rubbing underneath his sternum. “i...”

“I LOVE YOU,” Papyrus said, staring into his eye sockets with absolute conviction. “DON'T PUSH ME AWAY... DON'T... DO THIS TO YOURSELF EITHER.” His touches trailed across his ribs, gently down to caress the floating ribs. He massaged the juncture between the ribs and his spine, probing carefully and pressing his fingertips in with a drawn out sweeping motion through the path of the ribs before pushing back across to the juncture again.

Sans couldn't answer, and gave up on resisting. His soul was pulsing now, warm and irresistible. He felt the reverberations of his groan rumble past his mouth and suddenly Papyrus was pushing him, his back hitting the snow and one of Papyrus's hands supporting his head from colliding with the back of the station. Magic began channeling through his touch, wrapping across Sans' spine when Papyrus set a hand there. Sans writhed, unable to stop himself from pushing into the warmth of Papyrus's magic, needy and seeking pleasure. 

“Hnngh!” One of his hands flew to his fixed grin, as if to repress the sounds that sprung forth treacherously. He also attempted to still the lewd bucking of his hips, although with little success. His eyes lidded, and an unusual flush graced his cheekbones. His breathing was hitching, picking up heavily, “Hahhh... hah...”

Encouraged by the positive response, Papyrus suddenly pumped more of his magic into his touch, one hand pulling down his shorts and pressing against hotly across his sacrum. His other hand traveled up the spine and into the rib cage.

“I WANT TO SEE YOU FEEL BETTER, I WANT YOU TO BE MORE THAN JUST OKAY,” Papyrus told him, his magic unfurling and tendrils of it dug through his hips evoking more feelings of pleasure. Sans bucked, mouthing unspoken questions silently. Papyrus locked his teeth with his, infusing more magic into the simple movement before murmuring “BECAUSE I LOVE YOU.”

With the repeated declaration Papyrus finally grasped San's soul tenderly underneath his ribs, stroking deliberately, and funneled the largest rush of his own magic into the center of all of San's emotions. Sans screamed helplessly as his orgasm surged through him with Papyrus's magic, a tidal wave that crashed through all the emotional distress and drowned it in his brother's feelings of love and care. Papyrus continued to hold his sacrum as Sans arched and maintained the flow of magic through his brother's body, watching San's eyes roll up and blink rapidly through the shock of orgasm. 

Overly sensitive and exhausted, Sans couldn't help the occasional twitch that jump started across his bones as Papyrus finally let go of his soul. Physically and emotionally exhausted, he fell asleep almost instantaneously as his brother carefully gathered him up into his arms. Papyrus stayed like that for a few minutes, holding him tightly and nuzzling him. Digging his heels into the snow, Papyrus pulled himself up from under the guard station and carried Sans back to their house in Snowdin.

Waking up in the morning, feeling good for the first time in many mornings, Sans realized that Papyrus elected to fall asleep next to him in San's bed. Not for the first time, he felt his conscious twist darkly in his head and he sighed. He was the worst brother in the world. The only thing he could do now however, was to go through the day and pretend that the night didn't happen. As quietly as possible, trying to project a sense of stillness in his movements, Sans sat up.

Nervous and edgy, he gathered his magic to take a shortcut when Papyrus grabbed his hand, still halfway buried underneath sheets. Sans cringed internally when he saw the tired look on Papyrus's face, well aware that Papyrus must've been worn out from last night's events. Papyrus murmured in earnest, “PLEASE DON'T RUN FROM ME...”

San's soul twinged painfully, and he slowly climbed back into bed. “i'm sorry papy.”

Papyrus pulled him closer and buried his face into his side. Sans hugged him tightly, “i'm so, so sorry. i won't go. i... i promise.”

For the briefest second he thought he could see a soft ash-like butterfly flutter across Papyrus's skull, and he squeezed his brother protectively, feeling him fall back asleep. No, that doesn't matter at all.

“i love you papyrus, and i won't go.”

**Author's Note:**

> I can't believe no one's listening to Butterfly on Your Right Shoulder and didn't think of Sans. But then, I listen to the zoozbuh version pretty frequently and his translation of one of the lines was something like "What's leaking out these wounds, is it blood or is it love?" which meant my associational mind immediately glommed onto the "Sans Blood/Ketchup" conundrum in the fanbase. In any case, someone make a sans!loid for Butterfly on Your Right Shoulder!!! I'd love to see it, and I feel like the song fits him fairly well.
> 
> Also, I think this counts as crossing the perv rubicon... unless the perv rubicon is somewhere else? At least I've deliberately strolled past SOME point of no return. *climbs into the trash can and starts putting decorations on it*


End file.
